Many liquids and viscous fluids are packaged in compressible tubular containers comprising a tubular container body having a closed end and a dispensing outlet at an open end whereby dispensing is effect by compressing the wall of the container body. However, it is very difficult to control the flow of material from the dispensing outlet owing to a number of factors including the viscosity of the fluid; the presence of flow restriction elements, such as filters, porous tips, and the like; and the general difficulty of an individual in initiating a proper and consistent pressure on the exterior of the container body to provide a consistent and suitable flow while avoiding the application of too much pressure whereby fluid is prematurely and/or excessively dispensed. It is especially difficult to maintain a proper pressure for the full duration of the desired flow. In addition, difficulty arises because these compressible tubular containers, particularly for unit dose or one-time applications, are short in length and are held and pressed between the thumb and forefinger, whereby precision dispensing is wholly contingent upon the individual firmly holding the compressible tubular container between the fingers while compressing the container body.
These problems are magnified where the liquid or viscous fluid, or a component thereof, is contained within a crushable ampoule within the lumen of the tubular container. Here one must apply sufficient pressure to crush the ampoule, thereby overcoming the inherent resistance and strength properties of the ampoule wall, while avoiding too much pressure which will cause an eruption of the liquid or viscous fluid from the dispensing outlet concurrent with the crushing of the ampoule wall. These devices have yet another key concern as the ampoules are most often made of glass or another rigid, breakable material, especially a plastic material. Owing to the thin nature of the compressible container wall, it is not uncommon for the glass or plastic shards to penetrate the compressible tubular container wall, cutting into the fingers of the individual using the same. These piercings also provide opportunities for the liquid to leak out of the container.
Many developments have been made to address many of these problems, several of which have addressed multiple problems at the same time. For example, Regan (U.S. Pat. No. 6,315,165 B1), although not employing an ampoule, nonetheless provides better dispensing control through the use of a device having opposing jaw elements which have a flat surface which lies against and presses against the side walls of a crimped tube to force material out of the tube opening. While an improvement, since the pressure is uniform across the tube surface, this configuration still has flow control issues.
Similarly, many improvements have been made to those devices which employ an ampoule. For example, D'Alessio et. al. (U.S. Pat. No. 6,478,191 B1) teach the use of a barrier which covers the exterior portion of the tubular container corresponding to the point or area of compression. The barrier is typically a polymer film which is wrapped about the circumference of the tubular container. Alternatively, D'Alessio et. al. (US 2003/0080151 A1) and Morane et. al. (U.S. Pat. No. 3,964,643) teach the use of similar barrier materials which are wrapped around the exterior circumference of the ampoule, all of which lies within the lumber of the compressible tubular container. While effective, these developments only address the problem with shards cutting the user and/or allowing for leakage through the pierced tubular container walls. In the meantime, it adds costs of materials and manufacturing complexity. Furthermore, because is it part of the container, it too is disposed of once the materials are dispensed: thereby adding more waste into the waste stream.
Koreska et. al. (U.S. Pat. No. 4,784,506), on the other hand, provides for a reusable device whose reusable body incorporates a pair of opposing blades each having a tappet facing inward and offset to one another, whereby pressure applied to the blades causes the tappets to break the ampoule within the body of the device. However, once the ampoule is broken, dispensing is reliant upon the natural flow of the liquid and the absorptive properties of the absorbent tip. The device of Koreska et. al. does not need nor does it have any means for increasing pressure within the casing holding the ampoule to facilitate dispensing of the liquid. Rather, it merely requires the tappets to break the ampoule.
While the art has endeavored to address and has to a limited extent achieved success in addressing many of these issues; others still exist.
Accordingly, there remains a need for a device having an improved gripping structure which allows for a more controlled, manual dispensing of a liquid or viscous fluid material from a container associated with that device. In following, there remains a need for such a device which also and simultaneously provides for greater and controlled accuracy in the locus of the dispensing of the material.
Additionally, there remains a need for a device for use with containers of liquid or viscous fluid composition, especially those packaged as a unit dose, wherein the liquid or viscous fluid composition, or a component thereof, is contained within a crushable ampoule within the main container body, which device allows for the manual and controlled crushing of the ampoule without inadvertent dispensing of the contents and/or, as desired, the concurrent and controlled dispensing of the contents. Furthermore, there remains a need for such a device which avoids concerns with shards of the crushed ampoule piercing the container wall and injuring the user.
Furthermore, there remains a need for a dispenser handle for use with tubular containers, especially unit dose containers, which are simple and inexpensive to construct relative to prior art applicators and which are reusable.